1. Field of the Invention
This invention relates to an apparatus for measuring the starting torque of a bearing and more particularly to an apparatus which applies a known radial load and a known acceleration to a bearing to permit measurement of the starting torque of the bearing.
2. Description of the Prior Art
Low friction bearings are utilized in a variety of applications driven by electric motors. Because certain types of electric motors exhibit very low starting torque, bearing starting torque is of interest. In order to provide an accurate measurement of the starting torque of a to a bearing, a measuring apparatus must have the following characteristics:
1. Be sufficiently sensitive to measure the torque of a low friction bearing, PA1 2. Exert a sufficient radial load on the test bearing, and PA1 3. Not exert an inertial load which would give an erroneous indication.
Bearing manufacturers presently measure low friction bearing starting torque with the bearing under an axial load. While this type of test allows the use of a much simpler test apparatus, an axial load does not always provide a good simulation of an actual operating load. Thus, the torque values obtained in such a test could be misleading. Accordingly, it is desirable to provide a test apparatus that will closely simulate radial operating loads upon a test bearing.